I. Technical Field
In some aspects, the present disclosure relates to epoxidation chemistry and catalysts thereof. The present disclosure relates to new titanium silica catalysts for use in the epoxidation of an alkene or aralkene and methods of preparing the catalysts.
II. Description of Related Art
Titanium silica catalysts represent one of the most commonly used catalysts for the production of epoxidation products from alkenes. In the presence of a peroxide, the catalyst assists in converting a carbon-carbon double bond into an epoxide. In general, there are three primary types of reactions which will lead to the generation of an appropriate titanium silica catalyst. The first reaction involves grafting the titanium species directly onto an oxide surface. Such a mechanism works by directly treating the solid support with a titanium complex such as titanium tetrachloride. Next, an appropriate catalyst can be produced by the hydrothermal synthesis of Ti-silicates, such as the commercially available TS-1 and Ti-MWW. Finally, the titanium silicates can also be formed through the use of non-hydrolytic sol-gel routes such as those based upon alkyl halide elimination.
These methods produce catalysts which exhibit moderate activity due to metal leaching, the presence of other metals in the reagents and final products, or other factors. As such, the further development of epoxidation catalysts and methods of preparation are commercially useful.